<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>a 标点击后 hover 事件失效</title>
</head>
<style lang="css">
  a:hover{
    color: blue;
  }
  a:active{
    color: blue;
  }
  div {
    overflow: hidden;
  }
  .bb{
    overflow: hidden;
  }
</style>
<body>
  <div class="box">
    <a href="https://www.baidu.com">百度</a>
  </div>
  <div style="width:100px; height:100px; margin-bottom:100px;background:red;"></div>
  <div class="bb">
    <div style="width:100px; height:100px; margin-top:200px;background:blue;"></div>
  </div>
</body>
</html>